Software-configurable multi-function RF module
A configurable radio frequency system. The system includes: a plurality of radio frequency cells connected in a cascade. Each of the radio frequency cells includes an input switch connected to an input of the radio frequency system, an output switch connected to an output of the radio frequency system, and a plurality of elements, each of the elements being connected between the input switch and the output switch. The input switch and the output switch are configured, depending on their respective settings, to cause a radio frequency signal path from an input of the cell to an output of the cell to include one of the elements. The plurality of elements in each cell includes a band pass filter, an attenuator, a through path, an amplifier, and a mixer.
1. A system, comprising:
a first radio frequency cell;
a second radio frequency cell;
a third radio frequency cell; and
a fourth radio frequency cell;
one of the radio frequency cells comprising:
an input switch;
an output switch;
a first element, the first element being a member of a first functional group;
a second element, the second element being a member of a second functional group; and
a third element, the third element being a member of a third functional group,
the input switch and the output switch of each of the radio frequency cells being configured, depending on their respective settings, to cause a radio frequency signal path from an input of the radio frequency cell to an output of the radio frequency cell to include one of the first element, the second element, and the third element,
each of the first functional group, the second functional group, and the third functional group, being a different group selected from the set consisting of: filters, amplifiers, mixers, frequency multipliers, attenuators, and through paths,
the input switch comprising a switch with at least three throws, and
the output switch comprising a switch with at least three throws,
the first radio frequency cell, the second radio frequency cell, the third radio frequency cell, and the fourth radio frequency cell being connected in a cascade,
wherein:
the first element of the first radio frequency cell is a bandpass filter,
the second element of the first radio frequency cell is an attenuator,
the third element of the first radio frequency cell is a through path, and
the first radio frequency cell further comprises:
a fourth element, the fourth element being an amplifier; and
a fifth element, the fifth element being a mixer, and
the input switch and the output switch of the first radio frequency cell are further configured, depending on their respective settings, to cause the radio frequency signal path from the input of the radio frequency cell to the output of the radio frequency cell to include one of the fourth element, and the fifth element,
the system further comprising:
a field programmable gate array connected to, and configured to control, the input switch and the output switch of each of the radio frequency cells; and
one or more power detectors each connected to:
a respective output of one or more of the radio frequency cells, and
the field programmable gate array,
wherein the field programmable gate array is configured to detect failure of an element of the radio frequency cells, and, in response to detecting a failed element, to control the input switch and the output switch of the radio frequency cell including the failed element to cause the radio frequency signal path from the input of the radio frequency cell to the output of the radio frequency cell to bypass the failed element.
2. The system of claim 1 , wherein a radio frequency cell of the first radio frequency cell, the second radio frequency cell, and the third radio frequency cell further comprises a phase locked loop having an input connected to a reference input of the radio frequency cell and an output connected to a local oscillator input of the mixer, wherein the phase locked loop has a digital control input for controlling a ratio of:
a frequency at the output of the phase locked loop, to
a frequency at the input of the phase locked loop,
the field programmable gate array being connected to, and configured to control, the phase locked loop.
3. The system of claim 1 , wherein a bandpass filter of the bandpass and filters has a digital control input for controlling a passband center frequency of the bandpass filter, and
the field programmable gate array is connected to, and configured to control, the bandpass filter.
4. The system of claim 1 , further comprising a frequency reference,
wherein the frequency reference is connected to the reference input of two of the radio frequency cells.
5. The system of claim 1 , wherein:
the first element of the second radio frequency cell is a bandpass filter,
the first element of the third radio frequency cell is a bandpass filter,
the bandpass filter of the first radio frequency cell has a first passband center frequency,
the bandpass filter of the second radio frequency cell has a second passband center frequency, and
the bandpass filter of the third radio frequency cell has a third passband center frequency,
the first, second, and third passband center frequencies all being different.
6. The system of claim 1 , wherein the first radio frequency cell, the second radio frequency cell, and the third radio frequency cell are installed on, and connected to, a single printed circuit board.
7. The system of claim 1 , further comprising a power supply connected to, and configured to provide DC power to, each of the first radio frequency cell, the second radio frequency cell, and the third radio frequency cell.
8. The system of claim 1 , wherein the attenuator of one of the radio frequency cells has a digital control input for controlling the attenuation of the attenuator.
9. The system of claim 1 , wherein the bandpass filter of one of the radio frequency cells has a digital control input for controlling the bandpass filter.
10. The system of claim 1 , wherein the amplifier of one of the radio frequency cells has a digital control input for controlling the gain of the amplifier.
11. The system of claim 1 , wherein one of the radio frequency cells further comprises a phase locked loop having a reference input connected to a reference input of the radio frequency cell and an output connected to a local oscillator input of the mixer of the radio frequency cell.
12. The radio frequency cell of claim 1 , wherein a switch of the input switch and the output switch comprises a plurality of conductive traces and a plurality of pairs of solder pads, each pair comprising two solder pads separated by a distance corresponding to a separation between contacts of a surface-mount component, each of the solder pads being connected to one of the conductive traces, the conductive traces and solder pads being configured to establish, upon installation of a conductive component or capacitor across one of the pairs of solder pads, a radio frequency signal path corresponding to a setting of the switch.
13. The system of claim 3 , wherein the bandpass filter is a switched filter bank.
14. The system of claim 9 wherein a passband center frequency of the bandpass filter is controllable through the digital control input.
15. The system of claim 9 wherein a bandwidth of the bandpass filter is controllable through the digital control input.
16. The system of claim 9 wherein an order of the bandpass filter is controllable through the digital control input.
17. The system of claim 11 , wherein the phase locked loop has a digital control input for controlling the ratio of:
a frequency at the output of the phase locked loop, to
a frequency at the input of the phase locked loop.
18. A system, comprising:
a first radio frequency cell;
a second radio frequency cell;
third radio frequency cell; and
a fourth radio frequency cell;
one of the radio frequency cells comprising:
an input switch;
an output switch;
a first element, the first element being a member of a first functional group;
a second element, the second element being a member of a second functional group; and
a third element, the third element being a member of a third functional group,
the input switch and the output switch of each of the radio frequency cells being configured, depending on their respective settings, to cause a radio frequency signal path from an input of the radio frequency cell to an output of the radio frequency cell to include one of the first element, the second element, and the third element,
each of the first functional group, the second functional group, and the third functional group, being a different group selected from the set consisting of: filters, amplifiers, mixers, frequency multipliers, attenuators, and through paths,
the input switch is a cross-bar switch and the output switch is a crossbar switch, the first radio frequency cell, the second radio frequency cell, the third radio frequency cell, and the fourth radio frequency cell being connected in a cascade,
wherein:
the first element of the first radio frequency cell is a bandpass filter, the second element of the first radio frequency cell is an attenuator, the third element of the first radio frequency cell is a through path, and the first radio frequency cell further comprises:
a fourth element, the fourth element being an amplifier; and
a fifth element, the fifth element being a mixer, and the input switch and the output switch of the first radio frequency cell are further configured, depending on their respective settings, to cause the radio frequency signal path from the input of the radio frequency cell to the output of the radio frequency cell to include one of the fourth element, and the fifth element, the system further comprising:
a field programmable gate array connected to, and configured to control, the input switch and the output switch of each of the radio frequency cells; and
one or more power detectors each connected to:
a respective output of one or more of the radio frequency cells, and the field programmable gate array, wherein the field programmable gate array is configured to detect failure of an element of the radio frequency cells, and, in response to detecting a failed element, to control the input switch and the output switch of the radio frequency cell including the failed element to cause the radio frequency signal path from the input of the radio frequency cell to the output of the radio frequency cell to bypass the failed element.
19. The radio frequency cell of claim 18 , wherein the input switch and the output switch are configured to cause a radio frequency signal path from the input of the radio frequency cell to the output of the radio frequency cell to include, in order:
one of the first element, the second element, and the third element;
the direct conductive connection; and
another one of the first element, the second element, and the third element.
20. The radio frequency cell of claim 18 , wherein:
the input switch has a plurality of first terminals and a plurality of second terminals, and is controllable to connect each of the first terminals any of the second terminals;
the output switch has a plurality of first terminals and a plurality of second terminals, and is controllable to connect each of the first terminals any of the second terminals;
three of the second terminals of the input switch are connected, respectively, to the first element, the second element, and the third element;
three of the second terminals of the output switch are connected, respectively, to the first element, the second element, and the third element; and
at least one of the first terminals of the input switch is connected to one of the first terminals of the output switch.